Three's Company, Two's a Crowd
by Saucery
Summary: The multiverse makes them do it. Or, the one in which the author proves that when Dean Winchester, Jim Kirk and Sirius Black are stuck in a room, there's really only one thing they can do. A triple crossover: Supernatural/Harry Potter/Star Trek 2009.


**Dedication:** For LiveJournal's _murf1307_, whose reviews are ridiculously - perhaps criminally - inspiring.

**Translation:** Not. My. Fault.

* * *

><p><strong>THREE'S COMPANY (TWO'S A CROWD)<strong>

* * *

><p>They barely had time for introductions. <em>Sirius<em> barely had time for introductions. All he knew was that he'd tumbled into the Room of Requirement scarcely a moment before two others had joined him, one dark-haired and the other light, and both, inexplicably, American. ("Dean," the dark one had growled, gruff and already unbuttoning his jeans. "Jim," the other had husked, bright-eyed and hungry, as he'd pushed Sirius to his knees.)

Sirius was willing to go with anything, at the moment, including the idea that these men were just hallucinations his subconscious and the Room of Requirement had conspired to create, perfect and hard-bodied and slick with sweat - and it didn't matter what their names were, at all, except that he knew that if he wanted the most lush, sinful mouth in the _world_ on him, he'd call for Jim, and if he wanted that broad, beautifully callused grip, he'd call for Dean. Their names were just labels for the things he wanted to have, _needed_ to have, and they seemed just as desperate to give it to him, Dean fucking him hard, then harder, then _hardest_, Jim writhing beneath them, beneath _Sirius_, grinning like a lunatic and wanking himself off, wanking them _both_ off, the moving knuckles of his fist grazing Sirius's belly in soft, electric brushes that made Sirius tremble, that made them _all_ shake.

They'd come on the floor and on each other and _in_ each other more times than Sirius knew how to _count_, and it was only later, when their mutual fever had abated somewhat, that they finally stopped to catch their breath.

And Sirius stopped to _think_, or, well, think as much as a Gryffindor recently hit with a lust hex _could_ think, and it was then that he realized that hallucinations didn't normally stick around for the pillow talk.

Floor talk. Whatever. Apparently, the Room of Requirement had thought they didn't _require_ adequate bedding. Maybe it thought they didn't _want_any, and the fact that Sirius had always had that odd fantasy of scraping his knees on a stone floor surely had nothing to do with it.

Right. Nothing at _all_.

"So," said Sirius, barely stopping himself from hissing as he rubbed his stinging knees. "Er. You're both… American?"

"And you're underaged." Dean was still naked and flushed and glowing with sweat, like some kind of Greek god, but he was starting to look vaguely horrified. "You're underaged, aren't you?"

"Details, details." Jim's eyes crinkled merrily. "He knew what he was doing. Didn't you, kid?"

_Kid?_ "You look like you do this everyday."

"Well, not _this_, exactly, as in, I don't get dosed with sex pollen everyday. But I _do_ get dosed with _sex_ everyday. If it's a good day that doesn't involve getting blown out of the sky by aliens." He paused. "Okay, maybe even then. Sometimes _with_ the aliens."

_Aliens?_ Wait. Pollen? "Did you have a Herbology accident?"

Jim snorted. "That what they call it, here? Yeah, sure, why not. What about you, kiddo?"

Sirius was seriously about to _bristle_, but Dean beat him to it.

"Maybe you should stop calling him 'kiddo'," Dean gritted out, "given that you just had _your dick up his ass_."

"So did you." Jim raised his eyebrows. "At the same time, even."

Dean began to look _sick_.

"It's - it's fine," said Sirius, hurriedly, not because his arse _didn't_ hurt like a ripe, bruised, deeply _cored_ fruit, but because Dean looked like he might be one of those responsible types, maybe a Hufflepuff with younger brothers, or something. "I… I liked it." He was _not_ blushing. Sirius Black did not blush. "I liked all of it. A lot."

Dean was staring at him. At his _face_, and _only_ at his face, probably because they were still naked. At least the place was warm. "That ain't the point. You know that, right?"

"The _point_," Jim broke in, "was for us to get _off_, as quickly as possible, and get whatever crap we have in our systems out of our bodies before we hurt anyone we actually cared about. _You_ know that, right?"

Dean scowled.

Jim just lounged - how did anyone _lounge_ on the _floor_? - and smirked. Lazily. "What're you in for, anyway? Because you're clearly in for_something_."

"This - this was supposed to be the panic room. _Bobby's_ panic room, which - which I needed to be in because that damn incubus was after me, and - "

"An _incubus_?" Sirius sat up so quickly that his muscles - inside _and_ out - twinged. Ow. "That… that means you had to use sigils to keep it out, didn't you? Not just the usual sigils." He frowned. "Enochian?"

Dean _gaped_. "You know Enochian?"

"'Course I do. Advanced Charms _and_ History of Magic. The language of the supposed angels, I mean, obviously, they don't exist."

"Obviously," said Dean, slowly. His eyes were weird and _narrow_, but he also seemed faintly amused. "Go on."

"Yeah, go on." Jim was frankly _avid_. "All this mumbo-jumbo stuff sounds a hell of a lot like forcefields and inter-dimensional rifts, so I'm just gonna sit here and decode the metaphors."

"They're not metaphors." Think, Black, _think_ - there was that book dear old Father had on demons and sigils that he'd never let Sirius read, except that Sirius had read it, _anyway_ - "Hm. Enochian sigils. They're very strong. But if the incubus threatened to break them, they'd take you somewhere _else_, instead, somewhere - "

" - safe," Dean finished, looking impressed. "You're a bright ki - uh - person, Sirius."

"Person." Jim doubled over, laughing. "_Person_? Really?"

"Hey, I just - "

"Next, you'll be calling him an _entity_. No, wait, a _sentient being_."

"Does it even bother you that we just fucked a _teenager_?"

"Nope." Jim shrugged. "Not like it matters. I mean, you're both holograms."

Dean and Sirius stared at him.

"Really _interesting_ holograms. But still. No offense, seriously. I _like_ that one of you actually has a conscience and that the other one actually has a brain. Those metaphors? Awesome. Truly."

"Holograms," Dean repeated. Blankly. "_Holograms._"

"What are those?" Sirius had never heard of them, but, by Dean's reaction, they hadn't just been insulted and/or complimented; they'd been told something _else_. Something _important_.

"He thinks we're not real."

Not _real_? Sirius felt plenty real. Those brain-melting orgasms had been incredibly real, too.

Jim blinked, and then actually started to look _sheepish_. "Oh. Oh, shit. You didn't - you didn't know. Don't worry, I'll wipe the program when I leave. You guys won't remember a thing."

Was - was this bloke talking about an Obliviate? Sirius would much rather _remember_ those brain-melting orgasms.

"Look, I just - I don't normally use this holodeck, okay? I just didn't have the time to get to my favorite one, since there were, like, ants in my pants, bees in my knees, whatever - it was either this or start humping random cadets, which, yeah, no. Not happening."

"Let me get this straight," Dean rumbled, apparently completely unaware of his own pun, while Sirius tried to make sense of what the sodding hell Jim was _saying_. "You're from… the future. Where there are holograms. And holo_decks_."

"Yep. That. I'm not usually into twentieth-century fictional characters, so I steer clear of _this_ deck, okay?" Then, realizing what he'd just said, he backtracked. "Not that I'm not into _you_ guys, I'm _obviously_ into you, I was _literally_ into you, like, _minutes_ ago - "

"What are you _talking_ about?" Sirius threw up his hands. "Of _course_ we're real! That bastard Snape just hexed me! It was either fucking my best friend into next week and ruining everything, or hiding out in the Room of Requirement, and - look, I needed a place to hide out and also get off, and I knew this room would have _something_, although I was thinking more along the lines of sex toys, or - or - but it _has_ been known to pull _people_ in, too, across time and _space_, so maybe - "

"So maybe it pulled me from Bobby's panic room," said Dean, "and Jim from his - whatever it is, in the future. That's what you're saying?"

"Yes." Sirius drew a breath, relieved. "Yeah. Although, I mean, this is _very rare_, this is - it's usually only wizards or witches with very powerful magic that can manage something like this. _Dumbledore_ was the last wizard that managed to actually summon a real, live human being here, when he was _thirteen_, but I - this is amazing. I didn't think I could _do_ this."

"Okay." Jim nodded brightly. "Okay. Right. That's - that's exactly what this is."

Sirius slanted him a look. "You don't believe a word I just said, do you?"

"Uh? Sure. Sure, I do. Absolutely."

Dean grunted out what might've been a laugh. "Real convincing. Lemme tell you something, pal - you don't lie very well."

"Hey, at least I _can_ lie. Not like - " Jim cut himself off. A strange expression flickered across his face, possibly the first _real_ expression Sirius had seen on him so far, instead of that ever-present, insane grin. "I couldn't… couldn't let him find me like this. I'd - I'd do something we'd both regret."

"Tell me about it," Dean muttered. "He's so _pure_. I can't - " Dean _also_ cut himself off.

Oh. _Oh_. "The two of you, um, have best friends, too? That you, er. Like? Maybe?"

"People tend to like their friends." Dean had that grudgingly amused look on his face, again. "That's why they're friends."

"Well, _yeah_," said Sirius, impatiently. "But that's not what you mean, is it? Either of you."

"No," said Jim, quietly. "No, it isn't."

And then, they sort of just _sat_ there. For a while. Thinking about - the people they were thinking about. Sirius was thinking of Remus. Jim was thinking of his not-liar. Dean was thinking of his pure (virginal?) friend. It was _obvious_ who they were all thinking about, so obvious that Sirius was almost worried the Room of Requirement would haul _them_ in, too. Which, while it might've been another nice fantasy, would be an utterly_horrible_ reality. Because he did _not_ need Remus to walk in on him covered in some other bloke's spunk. In _two_ blokes' spunk.

No. Just - no.

Right. That was probably _why_ the Room of Requirement hadn't pulled the others in.

"Good call, Room," Sirius mumbled, dropping his head into his hands. "Excellent call. Thanks."

A few minutes later, Dean spoke up. "I know why _I'm_ still here. Why are _you_ still here?"

"Oh, man," said Jim. "That pollen? Takes at least six hours to work itself outta my system. So, you know." He gestured to himself, and, yeah, he was getting hard again. He was starting to look a little feverish, as well. "Takes a couple rounds, at _least_. Gets easier every time, but…" He hitched a shoulder. "You?"

"The curse of the incubus takes about that long to wear off, too."

They turned to look at Sirius.

"Um," said Sirius. "Same here."

"Coincidence?" Jim's eyes _gleamed_.

"I think not." For the first time this evening, Dean _chuckled_, and it was low and velvet-rough and sounded like Dean's stubble _felt_. Sirius hoped the twitch of his own cock wasn't too obvious. "_You_ think it's been programmed that way, don't you?"

"So sue me." Jim beamed. "Oh, wait, you can't. Hologram."

"You're a jackass, you know that?"

"Actually, I think he has a _very_ fine arse," Sirius blurted. "Er."

Jim turned to look at him. From under his _lashes_. "Why, thank you. I could arrange for you to enjoy it."

Sirius gulped. His throat was very, very dry. Getting drier by the second, even.

"He's _underaged_," said Dean, again, but Jim ignored him. He was crawling towards Sirius - on his hands and _knees_ - and he had the wettest, sweetest, _deadliest_ smile on his face.

"Then you can just sit over there and _watch_, Mister Morality. Not like that won't be fun, _too_."

Dean _growled_. Clenched his hands. Unclenched them.

And then, as Jim's hot, liquid mouth slid down around Sirius, Dean _moved_.

Sirius tilted his head back, closed his eyes, and felt that hard, scarred chest press against his back, those rough, callused palms slide down his stomach.

"Th-thank you," said Sirius, _quivering_, feeling the simmering heat in his blood rising to the surface once more, warming him up, moistening his skin, making him pant. He wasn't going to thank Snape for this. He _wasn't_ - "Oh, thank - "

"Hush," said Dean, gravel-deep and heavy, his voice a _weight_ in Dean's ear, implacable and _close_. And then Dean was kissing him, and Dean's hands were only gentle because they were _harsh_, gripping his thighs and parting them, _forcing_ them apart, so Jim could settle more easily between them, could hum and groan and make Sirius shudder, could make Sirius arch and make Sirius _burn_, could make his nipples harden and_ache_ for a touch, could make him gasp into Dean's kiss and _moan_, just moan, instead of calling the right -

- wrong -

- name.

* * *

><p><strong>fin.<strong>  
>Please review!<p> 


End file.
